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Water Hardness in 21663

Saint Michaels, Maryland · Talbot County

57 PPM
3.3 GPG
Soft
0Soft60120180300+
High Confidence — USGS Monitoring

Dataset updated March 9, 2026Matched to 4 water systemsTap readings can vary by utility zone, treatment, and plumbing. Methodology

Source context

How this ZIP reading is built

This ZIP reading is built from 4 matched water systems. When more than one system is matched, the displayed value is weighted toward larger known service populations when that data is available.

Source basis
3 USGS-backed sources
4 matched systems total for this ZIP; USGS monitoring is used where treated-water reports are unavailable.
Water source profile
Primarily groundwater
Groundwater commonly picks up calcium and magnesium after contact with rock and soil. This profile is weighted by known population served across matched systems.
Data recency
March 9, 2026
Dataset rebuilt March 9, 2026; individual utility reporting years can vary.

Hardness is a mineral-content reading, not a drinking-water safety rating. Use it for scale, appliance, and softener decisions; check your utility report or test your tap before sizing treatment equipment. See how we calculate local readings.

Water Systems Serving 21663

These are the systems matched to this ZIP code. The displayed ZIP value is weighted toward larger known service populations when population data is available.

4 water systems
PWSID is the public water system identifier. Data Source shows whether the hardness value comes from a treated-water report, USGS monitoring, or a local estimate; source year is shown when available.
Easton Utilities
MD0200003
Soft
44 PPMgroundwater17,357 servedHigh Confidence — USGS Monitoring
Town Of St. Michaels
MD0200006
Slightly Hard
104 PPMgroundwater2,650 servedHigh Confidence — USGS Monitoring
Town Of Trappe
MD0200007
Slightly Hard
104 PPMgroundwater1,200 servedEstimated — County Avg
Martingham Utilities Cooperative
MD0200004
Slightly Hard
104 PPMgroundwater675 servedHigh Confidence — USGS Monitoring

Nearby Zip Codes

216474821612482167648216244821653482166248216014821665482167148216545021638552161955

What This Means For You

Recommendations are based on the displayed ZIP hardness reading. Confirm your tap reading before sizing or buying treatment equipment.

Your Water Is Soft

Your water hardness is in the soft range. You likely don't need a water softener. Enjoy your naturally soft water!

Know your water hardness?

If you've tested your water or have your utility's CCR report, share your reading to help us improve accuracy for Saint Michaels, MD (21663).

Submit Your Data

Frequently Asked Questions

Is the water hard in Saint Michaels, MD (21663)?

The average water hardness in 21663 is 57 PPM (3.3 GPG), which is classified as soft.

Do I need a water softener in 21663?

At 57 PPM, your water is relatively soft. A water softener is generally not necessary.

Is hard water in 21663 safe to drink?

Water hardness itself is a mineral-content reading, not a drinking-water safety rating. Calcium and magnesium are naturally occurring minerals, but you should check your utility's Consumer Confidence Report for contaminant and compliance information.

How many water systems serve 21663?

Zip code 21663 in Saint Michaels, Maryland is served by 4 water systems.

Learn More About Your Water

Water Hardness Scale: PPM and GPG Chart

Use the USGS water hardness scale to compare PPM, GPG, and mg/L levels from soft to very hard water.

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How to Test Water Hardness at Home

Compare free lookups, soap tests, test strips, liquid drop kits, and lab tests for measuring water hardness.

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